I have the following two statements.  What is the difference?  What would you expect the results to be?  Are you surprised by what you get?

select 1
where convert(xml, '<foo>bar</foo>').value('/foo[1]', 'nvarchar(4)') = 'Bar'
go

select 1
where convert(xml, '<foo>bar</foo>').exist('/foo[.="Bar"]') = 1
go